I had the same problem with my setup except I was getting whine from the engine. I finally bought a ground loop isolator but one that plugged into the RCA jacks on the amp that connect to my computer and it competly solved the problem. Funny thing is if I don't turn on the computer I still get whine from the speakers.
So I guess there are two differen't types of ground loop isolators. The ones that connect to the power on an amp and ones that plug into the actual audio RCA source. Mine plugs into the audio source and I got it for 12 bucks from Walmart, well worth the investment.
By the way, can anyone explain how a ground loop isolator works?
Hmm, I tried a bit of digging in google, and the closest I found was this: http://www.epanorama.net/documents/g..._building.html
It's for radio antenna isolators, but I reakon the principle is the same. (?)
Also, I found a ground loop isolator for less then £15. It's about £4 to be exact, so I'm gonna get it anyway, so even if it doesn`t work, it's only £4. Link: http://custom1.farnell.com/cpc/produ...5Fid=AR7027066
By the way, I've only ever seen the type that plugs into the RCA's, aswell, never seen or heard of another type until now. I'm getting a alternator whine from the speakers from the speakers when my engine is running. In the meantime, I`m using my other amp, the one which doesn`t have any buzzing or noise, but I can`t have it too loud since it's now running at 2ohms (eg, 4 speakers on 2 channels), and It could fry some of the components in the amp if I crank it up too much.
Now youhave to remember that the RCA ground loop isolators (the ones I bought) are almost like a crossover and actually can filter out some of the sound you do want. I haven't tried the gound loop isolator that plugs into the amp but I am interested if anyone has tried it before please do post here and let us know if it's worth it.
Theres ur problem
Hard drives have magnetic fields!
Magnetic fields can cause noise!
I think the magnet in the hard drive is causing the noise!